A fuel manifold of a gas turbine engine distributes fuel from a fuel control system to fuel nozzles mounted on a support casing. Due to the high temperature environment, prior art manifolds of various types have disadvantages. For example, external flex tube manifolds are vulnerable to thermal distress, fuel leakage and fire hazard, and external transfer tube type manifolds which have a large number of parts suffer from problems of O-ring durability, fuel leakage, higher wetted-wall temperature and soak-back metal temperature which results in coke formation. In certain cases, a manifold is adapted to deliver a primary fuel flow which is in a small amount to starter fuel nozzles and a secondary fuel flow to the remaining fuel nozzles. There is always a challenge to provide a fuel passage configuration for the primary fuel flow in a small amount in such a high temperature environment.
Accordingly, there is a need to provide an improved fuel manifold for gas turbine engines.